few photos on ipad

iCloud is principally a file synchronisation service. As such, iCloud Photos will keep a copy of Photos stored on your iPad and other Apple devices - and will keep Photos synchronised between them.

It is important to note that, by design, iCloud Photos is not an independent archive. Deleting photos from your iPad will synchronise the deletion with iCloud and other devices that are synchronised via iCloud.

While it is possible to archive photos to a separate folder within iCloud Files, or other USB storage or Cloud service, you will have to do so manually. To do so, you will need to export your photos/videos from your Photo Library to a folder that you create in your iCloud file storage...

Using the native Files App, create a folder in iCloud - within which you will initially save a copy of your selected photos and videos.

Next, open your Photos App - and from your Library, tap to select the items that you wish to copy to iCloud file storage. When you have selected the items that you wish to copy, tap the Share button (a square with an upward-pointing arrow) at bottom-left of the Library window.

Tapping the Share button will expose an action menu; from the menu select Save to Files - and navigate to the iCloud folder that you have created - then tap Save. Your selected photos/videos will be copied to the folder that you have selected.

Don't try to copy all your photos/videos in one go - as this will be very slow and may fail due to insufficient system resources. Instead, copy across small batches.

When you have finished, check that all your photos are visible using the Files App. You should note that photos and videos that are not stored within the Photo Library cannot be accessed or viewed using the Photos App.

When you are happy that you have copied your photos/videos to the intended folder, only then is it safe to delete the original image files from your Photo Library.

You're very welcome.